Thanks for this video. I have been chasing this same problem in my 74 MGB all summer. My car would run fine for about 10 miles an then loose power and almost not run. After cooling down it would run fine again. Like you I thought it was an ignition problem, but changed everything with no change. Then I thought it might be a vacuum leak so I changed the manifold gaskets. After watching your video I pulled the HS4 carbs and sure enough the throttle shafts were badly worn. Just to see if it was my problem, I put a heavy coat of hi-temp grease on the shafts and reassembled the carbs. The car ran great!! Who says MGB and Triumph guys can't get along. Thanks again.
I never use those screw-type fuel hose clamps, because they can cut into the hoses, I use smooth fuel hose clamps which curl up away from the hoses at the outside edges. Also I only use Gates Barricade Bio-Fuel, (Ethanol Proof) rubber hose, 30R14 for carburettors or 30R9 for fuel injection. (I use this type of hose throughout the car).
Hi sometimes you can pull the choke out a bit to see if the engine improves. Also I have seen the spring break inside the distributor underneath the base plate.
Good idea pulling choke a bit over 40mph where it bogged down but my feeling is that he doesn't use timing light strobe dynamically and the real truth about classic cars is that many are really tired and an old distributor is junk as is an old carburettor they cannot be fixed easily if at all....replaced but not fixed.😊 Interesting show.
great video. as a kid i had a tr4 and not being a mechanic at 16 i screwed it up. learned mech on vw in later years. always check for vacuum leaks early on. at 75 years old i'll never get back into it but your channel is great fun to watch. thanks.
Another great troubleshooting video Elin! These mystery troubles sure take a lot of time to solve sometimes. I bought my 1974 XJ6 in 1999 and immediately had an issue. The car was running fine at idle but would die as soon as you tried to accelerate. It seemed like it was running out of gas. The usual checks were done, there seemed to be plenty of gas in the carb and the pumps were working fine. It took a long time but I discovered that on this car the 175 Stromberg carbs have a very small fine screen filter underneath the needle valve. It is about the size of a pencil eraser. Both of them were plugged with rust and dirt. This was very fine stuff that had got past the main fuel filters. I was thinking that perhaps that was what might be wrong with the TR4.
Also check the floats, if any needle valve is stuck open it will flood the carbs. I saw that gaskets have been changed on the carb and also float levels could be set wrong..
That is normally a sticky cable need a bit of grease but not at the top or it gets in the head. Engine sounded like tappers too tight. Or torn carb diaphragm.
That was a great troubleshooting video Elin. Nice result .. These sort of issues are the drawbacks of classic cars of course. Had that had an ECU you'd have seen the main issue straight away with a code reader. As for me, you can stick your ECU's and code readers where the sun don't shine 😅😅🌞🌑. Lovely car.. I'm very envious.
What an Awesome Vid. I love those triumphs. Almost bought an old Triumph Spitfire many years ago. The engine was in a basket but he didn't have a title for it so I passed it up. Bummer
Used to have a sun tuner and with the plugs going black it obviously running rich, I would check if the dizzy was advancing up by using a timing light which would show the timing advancing. As for the carbs I rember the same as su carbs their was oil in the tube above the needle to stop the needle rising to quick, it would make the car run bad if the mixture was already set rich causing fouling of the plugs...
The worn throttle spindles create a vacuum leak. Test first via a spray of carb cleaner or even a spray water at spindle shaft and carb body..if the idle changes usually increases if I recall, then you know you have worn throttle spindlesetc… which this car at least half the problem. Great video, Mr Yakov, you reveal many details which many of us Uber look. Thanks!
Good thing those bores weren't worn also. I had to have my CD150SE's reamed and a bushing installed, along with new shafts. Great job getting it all figured out.
I noticed the speedo bouncing quite a bit…something I see on my TR6. I have a new Speedo cable and will change it…is this the cause for the bouncy needle?
Very entertaining video, amazing how a messed-up mixture can cause the sparks to go crazy. Yes the speedometer is going crazy but it seems the oil pressure is all over the place too when you were driving ?
Excellent Excellent! All of what you were doing I need to know about my own TR6. My plugs 1-3 are way way too dark and the 4-6 are less than that but still too rich. I need all of what you just did done to my car. 👍 The OrangePeelr needs to Peel better!! Lol
I thought it was timing or coil or condenser but plugs were sooty so it's running rich but surely sloppy carb spindles allow more air so should be running weak. Could be wrong but these cars are so old there are multiple problems as needles jets floats are all worn badly and distributor is also worn .I wish triumph had used a larger single carburettor 😅😅😅😅
I noticed a misfire when you first were letting the engine idle. Also that the misfire got worse as the temperature increased. From my past experience your carbs are the type with temperature mixture compensation. I would be looking at these as a first point of any tuning. Also the dashpots should be checked for the correct quantity of oil. As this can cause these symptoms. Are the carbs correctly balanced. This is almost certainly a fuelling problem though so a complete examination of the fuel system including any vacuum lines should be a priority.
I assume you saw the full video already and saw that I moved to the fuel system later. But always you have to make sure your ignition system is in a good shape before you deal with fuel. Especially fuel mixture. Once tou move the timing or the points gap or anything, you have to redo your fuel settings. Therefore ignition first, fuel after. No temperature compensators on these early ZS
Wow! I am really impressed that you noticed the play in those shafts, Elin! That was really a surprising result in light of the way the engine was running. Very good diagnostic work. I just hope the owner replaces that speedo cable. I couldn't drive that car with that tail-wagging speedometer!
Does the TR4 have earthing straps on the engine, or does it get grounded through a different connection? I was wondering if that could be causing your issue - until the worn shafts came to light. Great and informative video, as always. Thanks for taking the time to make them. Stay safe out there.
I once had a friend replace an engine in my 1970 Dodge Dart (225 cu. in.). When I picked it up and drove home after a couple of miles it acted the same way but, a few miles later it quit. It wouldn't start and I tried everything (timing, points, etc.) I had to tow it home. The next day, it ran better when I removed the oil breather cap (thought I had solved the problem). Nope. After a test drive got the same results. Then while thinking about it I thought ....clogged muffler. crushed tailpipe....nope. Then I noticed the heat riser valve in the head pipe. The gasket was half way out at the back (towards the block). It was a metal gasker. I undid the bolts and found that the gasket was blocking half the exit to the headerpipe. I put it back the way it was supposed to go and it ran fine after that. I also found out he had replaced my 3 core radiater for a 2 core radiater to use in his 'stock car'. Some friend he was.
The ridiculously annoying ads are so bad that even if I wasn't hovering over the skip ads button so I never see what ads they are, if I DID, I'd NEVER buy any of the products out of anger and principal. Too bad Musk doesn't buy and fix UA-cam!!
You keep saying the advance has already opened at tick over that’s incorrect if the dissy is in good condition as the springs are there to stop the Bob weights from opening up till higher RPM all details will be in the manual of rpm ranges
I think with a new exhaust the car will driving much better, the engine need time for gas change. Wrong air is a problem what are most forget, but you found it.
I think it needs a new stripper cap you could have a break in The Wire between the Jupiter cap and the wires going to the spark plugs maybe change the spark Leeds
I forgot to mention something. I have always thought that the exhaust and intake valves were always fully closed at TDC. I am a little confused with what you said about one valve being open at TDC. At ignition both valves must be closed and then at the beginning of the intake stroke the intake valve opens. During the exhaust stroke the exhaust valve opens and I guess depending on the engine the exhaust valve has closed just as the piston reaches TDC. Much probably depends on whether an engine is an interference design or free wheeling, and domed or flat pistons etc.
The spec is: Intake opens 17 degrees BTDC Intake closes 57 degrees ABDC Exhaust opens 57 degrees BBDC Exhaust closes 17 degrees ATDC The frame between 17 before and 17 after TDC is when the valves overlap. They are both a little bit open. During those 34 degrees the piston doesn’t move much as the crank pin is at it’s peak as well and the movement is more horizontal than vertical. The valves on Triumph engines do not interfere with the pistons even if the cam timing is way off.
Well this is the second video I’ve watched that you’ve posted and on both cars especially with this one why have you loosened the dissy off had the owner told you he’d altered the timing? No! He’d obviously been messing with this that and the other from what he’d told you , he’d mentioned playing with the jets/ mixture now the plugs were very sooty / black a tell tail way to rich and if so will not burn correctly! The exhaust must have smelled of petrol! Especially when you took the tops off and saw the difference in the jet heights , as you probably know you screw up the jets till just touch pistons the turn down equal amount of both jets about 1&12 to 2 full turns for the engine to start then go on and tune like you did, you’ve really gone a long way round to get to the problem that it’s running to rich because the last guy to play with it didn’t know what he was doing! I hope you don’t charge by the hour !!
Omg 😱I hope you don’t charge by the hour ? You got there in the end by way of the part’s canon 😢 all that messing about with the ignition system and time wasting after checking out it was fine you continue to go down the rabbit hole 😢 the black spark plugs when you first took them out was the biggest clue because a too rich fuel mixture corses miss fire , then you don’t tell us all the truth of what caused the too rich mixture which was the jets were set wrongly and was not the fault of worn spindles shafts because worn spindles will make a mixture weak not richer, so the most important part for beginners to learn on setting up the mixture by setting the jets correctly you missed out and I think you did that deliberately! So people won’t know the real reason for the misfire which is why the car was brought to you in the first place! But on the plus side for your video I did enjoy the part of you using the scope machine because I had one similar to that but an lot older type gifted to me 30 years ago, but never found the need to use it yet even though Ive 5 cars ranging from 1934 to 1972 😀 still all in all a very interesting even though misleading video was still entertaining for an old mechanic of well over 70 years of age ! So in other words these types of cars are what I grew up with 😊
Thanks for this video. I have been chasing this same problem in my 74 MGB all summer. My car would run fine for about 10 miles an then loose power and almost not run. After cooling down it would run fine again. Like you I thought it was an ignition problem, but changed everything with no change. Then I thought it might be a vacuum leak so I changed the manifold gaskets. After watching your video I pulled the HS4 carbs and sure enough the throttle shafts were badly worn. Just to see if it was my problem, I put a heavy coat of hi-temp grease on the shafts and reassembled the carbs. The car ran great!! Who says MGB and Triumph guys can't get along. Thanks again.
I never use those screw-type fuel hose clamps, because they can cut into the hoses, I use smooth fuel hose clamps which curl up away from the hoses at the outside edges. Also I only use Gates Barricade Bio-Fuel, (Ethanol Proof) rubber hose, 30R14 for carburettors or 30R9 for fuel injection. (I use this type of hose throughout the car).
Hi sometimes you can pull the choke out a bit to see if the engine improves.
Also I have seen the spring break inside the distributor underneath the base plate.
Good idea pulling choke a bit over 40mph where it bogged down but my feeling is that he doesn't use timing light strobe dynamically and the real truth about classic cars is that many are really tired and an old distributor is junk as is an old carburettor they cannot be fixed easily if at all....replaced but not fixed.😊 Interesting show.
My favourite job rebuilding and balancing carbs in the day.
great video. as a kid i had a tr4 and not being a mechanic at 16 i screwed it up. learned mech on vw in later years. always check for vacuum leaks early on. at 75 years old i'll never get back into it but your channel is great fun to watch. thanks.
So much valuable information for TR owners! I learn something new from each video. Great job Elin!
Another great troubleshooting video Elin! These mystery troubles sure take a lot of time to solve sometimes. I bought my 1974 XJ6 in 1999 and immediately had an issue. The car was running fine at idle but would die as soon as you tried to accelerate. It seemed like it was running out of gas. The usual checks were done, there seemed to be plenty of gas in the carb and the pumps were working fine. It took a long time but I discovered that on this car the 175 Stromberg carbs have a very small fine screen filter underneath the needle valve. It is about the size of a pencil eraser. Both of them were plugged with rust and dirt. This was very fine stuff that had got past the main fuel filters. I was thinking that perhaps that was what might be wrong with the TR4.
Also check the floats, if any needle valve is stuck open it will flood the carbs. I saw that gaskets have been changed on the carb and also float levels could be set wrong..
tracking HT leads are a common problem and can be spotted in a dark garage.😮😅
Nice job. Originally I was thinking cam timing but you did find the core fault. Nothing like dealing with long time mechanical wear and fatigue.
You are truly amazing Elin
Great job as always he should have changed the Speedo cable that bouncing around would drive me crazy.
that speedometer would drive me CRAZY
Unfortunately it is a very common problem for TR4 speedometers
@@RustyBeauties is it difficult to repair?
I watched a video of upgrading the components of Smiths speedos and I'll be doing it for my GT6 speedo.@@RustyBeauties
That is normally a sticky cable need a bit of grease but not at the top or it gets in the head. Engine sounded like tappers too tight. Or torn carb diaphragm.
Me too 😂
... Your stamina in problem solving is admirable ... If I lived in Canada I would bring my car for sure ...
First 😉 Nice Job. Yeah, those throttle shafts were really bad.
First to like your First and +1 for the algorithm
That was a great troubleshooting video Elin. Nice result .. These sort of issues are the drawbacks of classic cars of course. Had that had an ECU you'd have seen the main issue straight away with a code reader. As for me, you can stick your ECU's and code readers where the sun don't shine 😅😅🌞🌑. Lovely car.. I'm very envious.
What an Awesome Vid. I love those triumphs. Almost bought an old Triumph Spitfire many years ago. The engine was in a basket but he didn't have a title for it so I passed it up. Bummer
Used to have a sun tuner and with the plugs going black it obviously running rich, I would check if the dizzy was advancing up by using a timing light which would show the timing advancing. As for the carbs I rember the same as su carbs their was oil in the tube above the needle to stop the needle rising to quick, it would make the car run bad if the mixture was already set rich causing fouling of the plugs...
Twin side draft Webber’s would be great
Well done sir!
crazy man buns, and buds
The worn throttle spindles create a vacuum leak. Test first via a spray of carb cleaner or even a spray water at spindle shaft and carb body..if the idle changes usually increases if I recall, then you know you have worn throttle spindlesetc… which this car at least half the problem. Great video, Mr Yakov, you reveal many details which many of us Uber look. Thanks!
Great job!
Good thing those bores weren't worn also. I had to have my CD150SE's reamed and a bushing installed, along with new shafts. Great job getting it all figured out.
Good job 👍
I always used an exhaust gas analyzer.
Amazing work 😊
Thanks for the video Elin. I’m having a similar problem with my TR6, so I’ll go through the same process.
I have found that ethanol fuel has a bad habit of varnishing over the paper in fuel filters, so I no longer use paper filters.
That’s interesting to know, so thanks for sharing 👍👍❤
I noticed the speedo bouncing quite a bit…something I see on my TR6. I have a new Speedo cable and will change it…is this the cause for the bouncy needle?
Haven’t watched it all but I think fuel pump or float height !
Regards,
Sandy 🔧🏴
You’re correct a fuel problem one could see that from the very beginning 👍👍
If I understand, the air leaks at the throttle shaft caused a rich condition that fouled the plugs showing up on the oscilloscope?
An air leak will cause the opposite effect and make it weaker not richer
Very entertaining video, amazing how a messed-up mixture can cause the sparks to go crazy.
Yes the speedometer is going crazy but it seems the oil pressure is all over the place too when you were driving ?
Fabulous video, of a great car, and great work finding and fixing the problem!
Excellent Excellent! All of what you were doing I need to know about my own TR6. My plugs 1-3 are way way too dark and the 4-6 are less than that but still too rich. I need all of what you just did done to my car. 👍
The OrangePeelr needs to Peel better!! Lol
Also change the coil, they are cheap anyway.. But my money is on the carbs set up bad when you drove it
Well my money was on coil or condenser, good work.
I thought it was timing or coil or condenser but plugs were sooty so it's running rich but surely sloppy carb spindles allow more air so should be running weak. Could be wrong but these cars are so old there are multiple problems as needles jets floats are all worn badly and distributor is also worn .I wish triumph had used a larger single carburettor 😅😅😅😅
I noticed a misfire when you first were letting the engine idle. Also that the misfire got worse as the temperature increased. From my past experience your carbs are the type with temperature mixture compensation. I would be looking at these as a first point of any tuning. Also the dashpots should be checked for the correct quantity of oil. As this can cause these symptoms. Are the carbs correctly balanced. This is almost certainly a fuelling problem though so a complete examination of the fuel system including any vacuum lines should be a priority.
I assume you saw the full video already and saw that I moved to the fuel system later. But always you have to make sure your ignition system is in a good shape before you deal with fuel. Especially fuel mixture. Once tou move the timing or the points gap or anything, you have to redo your fuel settings. Therefore ignition first, fuel after. No temperature compensators on these early ZS
Exactly, spot on he doesn’t half go round the houses the long way round to get to the front door!🤣🤣🤣👍
Great work Elin
Wow the oil pressure is off the clock 😮
Great video congrats !!
That was great diagnostics, and you did a great job to find that problem in the carbs. Another happy owner of a great looking car.
Wow! I am really impressed that you noticed the play in those shafts, Elin! That was really a surprising result in light of the way the engine was running. Very good diagnostic work. I just hope the owner replaces that speedo cable. I couldn't drive that car with that tail-wagging speedometer!
my 1850 dolomite is very similar, but i dont need to drive it to make it perform this way
🤣🤣🤣
So with the air leak around the throttle shafts, since it is on the manifold side does it make the mixture Rich or Lean?
Weak
Great video!!!
very good video
Ngk is the best. But great troubleshooting, ive never seen an oscilloscope in action before.
Loved this video as much as all the others, which is a lot!
Does the TR4 have earthing straps on the engine, or does it get grounded through a different connection? I was wondering if that could be causing your issue - until the worn shafts came to light. Great and informative video, as always. Thanks for taking the time to make them. Stay safe out there.
I once had a friend replace an engine in my 1970 Dodge Dart (225 cu. in.). When I picked it up and drove home after a couple of miles it acted the same way but, a few miles later it quit. It wouldn't start and I tried everything (timing, points, etc.) I had to tow it home. The next day, it ran better when I removed the oil breather cap (thought I had solved the problem). Nope. After a test drive got the same results. Then while thinking about it I thought ....clogged muffler. crushed tailpipe....nope. Then I noticed the heat riser valve in the head pipe. The gasket was half way out at the back (towards the block). It was a metal gasker. I undid the bolts and found that the gasket was blocking half the exit to the headerpipe. I put it back the way it was supposed to go and it ran fine after that. I also found out he had replaced my 3 core radiater for a 2 core radiater to use in his 'stock car'. Some friend he was.
The ridiculously annoying ads are so bad that even if I wasn't hovering over the skip ads button so I never see what ads they are, if I DID, I'd NEVER buy any of the products out of anger and principal. Too bad Musk doesn't buy and fix UA-cam!!
You keep saying the advance has already opened at tick over that’s incorrect if the dissy is in good condition as the springs are there to stop the Bob weights from opening up till higher RPM all details will be in the manual of rpm ranges
Nope. There are charts in the manual telling you which weights advance how much at what RPM. ALL of them start advancing at 500RPM
I think with a new exhaust the car will driving much better, the engine need time for gas change. Wrong air is a problem what are most forget, but you found it.
I think it needs a new stripper cap you could have a break in The Wire between the Jupiter cap and the wires going to the spark plugs maybe change the spark Leeds
I forgot to mention something. I have always thought that the exhaust and intake valves were always fully closed at TDC. I am a little confused with what you said about one valve being open at TDC. At ignition both valves must be closed and then at the beginning of the intake stroke the intake valve opens. During the exhaust stroke the exhaust valve opens and I guess depending on the engine the exhaust valve has closed just as the piston reaches TDC. Much probably depends on whether an engine is an interference design or free wheeling, and domed or flat pistons etc.
The spec is:
Intake opens 17 degrees BTDC
Intake closes 57 degrees ABDC
Exhaust opens 57 degrees BBDC
Exhaust closes 17 degrees ATDC
The frame between 17 before and 17 after TDC is when the valves overlap. They are both a little bit open. During those 34 degrees the piston doesn’t move much as the crank pin is at it’s peak as well and the movement is more horizontal than vertical.
The valves on Triumph engines do not interfere with the pistons even if the cam timing is way off.
Your correct that both valves are fully closed at TDC
Hi Elin, did it still run well with the air cleaner fitted?
Well this is the second video I’ve watched that you’ve posted and on both cars especially with this one why have you loosened the dissy off had the owner told you he’d altered the timing? No! He’d obviously been messing with this that and the other from what he’d told you , he’d mentioned playing with the jets/ mixture now the plugs were very sooty / black a tell tail way to rich and if so will not burn correctly! The exhaust must have smelled of petrol! Especially when you took the tops off and saw the difference in the jet heights , as you probably know you screw up the jets till just touch pistons the turn down equal amount of both jets about 1&12 to 2 full turns for the engine to start then go on and tune like you did, you’ve really gone a long way round to get to the problem that it’s running to rich because the last guy to play with it didn’t know what he was doing! I hope you don’t charge by the hour !!
❤❤❤
Dr Carburetor would be pleased.😂
Well, you did help, sending me in the right direction for new shafts! Thanks!
Sounds like something is pulling the voltage down in the coil. That would definitely lower power
I surprised myself. It was low Kv on the secondary. But I still don’t know what is pulling it down
Really enjoyed the video. Do you think it was the float level that was the issue. Or the worn butterfly shaft.. JMD
Just badly adjusted jet setting making the air to fuel ratio completely wrong!
Seems like the fuel tank breather pipe is blocked.
Isn't that normal? LOL!
Condenser?
Not your problem, but did you notice some upside down springs on this head?
I hope that paper wasn't important.
LOL, I picked it up on the way back. It was just an email printout, but I didn't want to litter.
Omg 😱I hope you don’t charge by the hour ? You got there in the end by way of the part’s canon 😢 all that messing about with the ignition system and time wasting after checking out it was fine you continue to go down the rabbit hole 😢 the black spark plugs when you first took them out was the biggest clue because a too rich fuel mixture corses miss fire , then you don’t tell us all the truth of what caused the too rich mixture which was the jets were set wrongly and was not the fault of worn spindles shafts because worn spindles will make a mixture weak not richer, so the most important part for beginners to learn on setting up the mixture by setting the jets correctly you missed out and I think you did that deliberately! So people won’t know the real reason for the misfire which is why the car was brought to you in the first place! But on the plus side for your video I did enjoy the part of you using the scope machine because I had one similar to that but an lot older type gifted to me 30 years ago, but never found the need to use it yet even though Ive 5 cars ranging from 1934 to 1972 😀 still all in all a very interesting even though misleading video was still entertaining for an old mechanic of well over 70 years of age ! So in other words these types of cars are what I grew up with 😊